Liquid crystal display devices are widely used for display devices ranging from large-sized display devices such as television sets to small-sized display devices such as mobile phones. Therefore, the development of liquid crystal display devices is intended to achieve cost reduction or to provide high-value added liquid crystal display devices. In recent years in particular, there has been a growing interest in global environment and the development of liquid crystal display devices consuming less power has thus attracted attention.
Technique for reducing power consumption in a liquid crystal display device is disclosed in Patent Document 1. Specifically, a liquid crystal display device is disclosed in which all data signal lines are electrically separated from a data signal driver in an inactive period where all scan lines and data signal lines are in a non-selection state, so that a high impedance state is obtained.